Air-conditioning system



Feb 7, 195% R. c. SCHLJCHTIG 2 9 AIR CONDITIONING SYSTEM Filed Jan. 29,1946 3 Sheets-Sheet 1 fly 2 INVENTOR Feb, 7, 19@ R. c. KSCHLECHTHG AIRCONDITIONING SYSTEM Filed Jan. 29, 1946 3 Sheets-Sheet INVENTOR. @0601?C ficfi/iafifig Feb. 7, 19% R. c. SCHLICHTEG AIR CONDITIONING SYSTEM 3Sheets-Sheet 5 F'i1ed Jan. 29, 1946 INVENTOR. fia/ph 6. Sch/ic/zfig; BY

Patented Feb. 7, 1950 UNITED STATES PATENT OFFICE AIR-CONDITIONINGSYSTEM Ralph C. Schlichtig, Dishman, Wash.

Application January 29, 1946, Serial No. 643,992

Claims.

The present invention relates to an air conditioning system and isparticularly concerned with a mechanical and thermo system fortransferring heat and moisture into and out of a building or enclosure.It is the principal purpose of my invention to provide a system of thecharacter described wherein the ratio of heat delivered is relativelyhigh when compared with the heat equivalent of the mechanical energyused in bringing the temperature of the air in a confined space orenclosure to the desired level.

It is also a purpose of this invention to provide in such a system anovel means for replacing the confined air with fresh air.

It is a further purpose of this invention to provide a system of thecharacter hereinbefore described wherein the humidity of the enclosedair can be brought to the desired percentage in a simple manner.

In carrying out the foregoing purposes of my invention, the constructioncontemplated is such as to employ relatively small moving parts whencompared to the devices now in use, the moving parts being free of anyreciprocating parts so as to reduce friction. The system is applicableto both heating and cooling of the enclosed space by simple change ofposition of vanes in air passages. The apparatus contemplated also usesa low compression ratio, to make thick confining walls unnecessary. Thetemperature ranges of the expanding and compressed air which is used asthe working substance are kept at a minimum so as to secure a highthermodynamic efiiciency.

The system is also so constructed that in starting a small load isplaced on the prime mover so that the prime mover need not be heavymerely to start.

The nature and advantages of my invention will appear more fully as thedescription proceeds in connection with the accompanying drawingswherein a preferred form of the invention is shown. It should beunderstood, however, that the drawings and description are illustrativeonly and should not be considered as limiting the invention exceptinsofar as it is limited by the claims.

In the drawings:

Fig. 1 is a schematic diagram showing the cycle of the heat exchangesystem;

Figure 2 is an enlarged sectional view showing the turbine andcompressor assembly employed;

Figure 3 is an edge view of one of the rotors embodied in the turbineand compressor assembly; and

Figure 4 is a view in side elevation of the rotor.

tinues in the conduit 9.

The schematic diagram shown in Figure 1 illustrates the vanes as set foroperation of the system as a heating plant. Fresh air is taken into thesystem at 5. This air passes through a counter-flow heat exchanger 6 inthe passages I. In so doing, the fresh air becomes heated to near roomtemperature by robbing heat from an opposing stream of air which ispassed in the opposite direction through passages 8 of the heatexchanger 6. The warmed air from the passages i then is directed througha conduit 9 past a mixer l0 which is adapted to move part of the freshair out of the conduit 9 and into the enclosure or room to be heated.The mixer also removes a like volume of stale room air from the room andmixes it with the fresh air that con- The mixer is a slowly turningwheel with wide radial fins operating in a chamber which is open at itstwo opposite sides.

The preheating of the incoming air is of particular value in keeping thecompressor size and speed down where the difference between theenclosure to be heated and the surrounding air is great. For example, ifthis temperature is as much as 20 degrees centigrade, the air taken intothe system would have to be heated several degrees more than 20 degreesin order to give up heat to the warm enclosure. If a proposed compressorwould Warm the air only 15 degrees centigrade, the air must be preheatedseveral degrees more than 5 degrees centigrade in order to make thetotal temperature rise sufficient. The heat exchange is therefore vitalto maintain in order to keep the compressor size and power needsreasonable.

The conduit 9 opens into a moisture absorber H where the humidity of theair is lowered to the desired level. The air, after leaving the moistureabsorber H, passes through a conduit I2 to an inlet l3 to a compressorM. The compressor has a rotor I5 therein which imparts to the air a veryhigh velocity. This compressor operates substantially on the principleof the aspirator pump shown in my prior application Serial No. 618,885,filed September 27, 1945. The rotor l5 discharges the air at high speedinto a stationary diffuser 16 where the kinetic energy of the air isconverted to pressure energy. The compression is substantially adiabaticso that the temperature of the air is elevated considerably above roomtemperature when it is discharged into the outlet conduit I! from thediffuser IS. The conduit ll leads to a second counter-flow heatexchanger l8 where the excess heat of the compressed air is transferredfrom the air in the passages l9 to air in passages of the heatexchanger. The air in the passages 20 is normally the room air and it isdirected into the passages 20 by a conduit 2| and discharged back intothe room space through a conduit 22.

The air leaving the passages 19 is still compressed, although cooled toa substantial degree. Since the moisture has been removed from the airin the absorber H, the cooling of the air further as it passes throughthe passages 8 of the heat exchanger 6 does not result in condensationof any moisture. The passages 19 are connected to the passages 8 by theconduit 23.

The air from the passages 8 is directed through a conduit 24 to a motordriven rotor 25. The air by the time it enters the conduit 25 is loweredto nearly out-of-doors temperature, but it is still compressed two tothree pounds per square inch (ten to sixteen centimeters if measured bya mercury column), above atmospheric pressure when it reaches the rotor2 5. This-rotor is-driven by a motor 26. The rotor 25 converts thepressure ener y of the air from the conduit 24 into velocity-energy andthe air at the high velocity is directed against the vanes of theturbine rotor 21. Further velocity energy in addition to that due tothepressure energy of the air in the conduit 24 is imparted to the airby the motor 26 which drives the rotor 25 at a high speed. The airstream is thus expanded adiabatically through the elements 25 and 27.The rotor 21 is directly connected by a shaft 28 to the compressor rotor15 so-that the expansion of air through the elements 25, 2! drives thecompressor. Also, the expansion of the air lowers its temperature tobelow that of the temperature out'of doors, and the cold air from theturbine rotor 21 is discharged through a conduit 29 to the exterior.

Figure 2 of the drawings shows the construction of the turbinecompressor unit, and Figures 3 and 4 illustrate the manner of mountingthe vanes upon the rotor. In order that the order of the pressure andvelocity changes brought about in the turbine andthe compressor maybetter be understood, I will describe briefly the operation. Airentering the turbine unit through the conduit 24 will be at a highpressure pH when the mechanism is in operation. The pressure is of theorder of ten to sixteen centimeters of mercury. When starting the rotor25 by the motor 26, the pressure in the conduit 24 will not yet be builtup. Centrifugal force will first build up pressure at the circumferenceof the rotor 25. The air passes through the passages between the fins 30that are set radially in the rotor. The

passages are restricted so that they are smaller toward the right asviewed in Figure 2. Thus the velocity of the air must be greater at theright hand side of the rotor 25 than at the left. The fins 30 are so setthat the air is directed sharply in the direction of rotation by theslope of the fins. Therefore, the surface movement of the rotor plus theslope of the fins gives a total velocity to th air which is much greaterthan that of the rotor surface itself. In addition, after the device isin operation a considerable pressure will exist in the conduit 24 whichwill further speed up the air velocity at the right hand side of the:-rotor 25. The air stream then passes through the vanes 3| of theturbine rotor 21. These vanes are so set as to produce expanding slotsfrom right to left as illustrated in Figure 2 of the drawings. The rotor21 is turned by th energy of the air and in turn operates the shaft 28to drive the compressor rotor I 5. The

air is discharged from the rotor 27 into the conduit 29 preferably atabout atmospheric pressure.

The air entering the compressor at [3 is substantially at atmosphericpressure. The centrifugal force due to the rotation of the rotor 15builds up the pressure at the inlet to the rotor and air is drawnthrough the passage between the vanes of the rotor i5 because of thepartial vacuum created at the right hand ends of the passages betweenthe vanes by the Bernoulli effect. Thus, the air is given a high forwardvelocity through the passages between the vanes of the rotor I5. To thisvelocity is added the velocity of the rotor itself and the airtravelling at this relatively high velocity is fed into the expandingpassages of the diffuser Hi. The diffuser, of course, is stationary andacts to change the velocity energy of the air to pressure energy in theconduit H.

The vapor absorbing solution employed in the dehumidiiyer H isregenerated in a boiler 34. Heat may be supplied by a heating element 35and the'steam thus liberated can be utilized in heating a hot water tank36. The condensed steam may, if desired, be collected for soft water.Any vapor needed for bringing up the relative humidity of the room airmay be permitted to escape at the outlet 31.

When the system is used to cool the enclosure, the'only necessary shiftis to change the position of the valves 37, 38 and 39 so as to directair from the conduit 22 to the outside and to direct the cool dry airfrom the conduit 29 into the enclosure. No vapor will he wanted, ofcourse, so the valve 3? willbe closed.

Having thus described my invention, I cl-aim:

1. A method of conditioning the air of an enclosed space which comprisesdrawing in air from a space outside the enclosure then drying andcompressing, substantially adiabatically, air so drawn in, transferringheat from the compressed air to a counter stream of air drawn from theenclosed space, thereafter transferring additional heat from thecompressed air to the air drawn in before it is compressed, andexpanding, substantially adiabatically, the cooled compressed air,discharging the expanded stream to one space and discharging the counterstream to the other space.

2. A method of heating the air of an enclosed space which comprisesdrawing in air from a space outside the enclosure then drying andcompressing, substantially adiabatically, air so drawn in, transferringheat from the compressed air to a counter'stream of air drawn from theenclosed space, thereafter transferring additional heat from thecompressed air to the air drawn in before it is compressed, andexpanding, substantially adiabatically, the cooled compressed air,adding at least part of the water taken from the air drawn in by dryingto the air in said enclosure, discharging the expanded cooled air to theouter space, and discharging the counter ing the expanded air into theenclosure and discharging the counter stream of air to a space outsidethe enclosure.

4. A method of conditioning the air of an enclosed space which comprisesdrawing in air from a space outside the enclosure, interchangin part ofthe air drawn in for air in said enclosure then dryin and compressing,substantially adiabaticall'y, air so drawn in, transferring heat fromthe compressed air to a counter stream of air drawn from the enclosedspace, thereafter transferring additional heat from the compressed airto the air drawn in before it is compressed, and expanding,substantially adiabatically, the cooled compressed air, discharging theexpanded stream to one space and discharging the counter stream to theother space.

5. Apparatus for conditioning air of an enclosed space comprising an airinlet duct extending into said space from an outer space, an air ductsection in heat exchange relation to said duct adjacent to its entryinto the enclosed space, air transfer means connected to said inlet ductfor exchanging part of the air in said inlet duct for part of the air inthe enclosed space after the air has passed beyond the heat exchangeduct section, means to extract water vapor from the air in the inletduct after the air has passed the connection with said transfer means,power driven means for adiabatically compressing air, receiving the airfrom said inlet duct, a second air duct receiving the air from saidcompression means, another air duct in heat exchange relation to saidlast named air duct and receiving air from said enclosed space, wherebyto extract heat from the compressed air, said second air duct leading tosaid air duct section whereby to deliver heat from the compressed air tothe air flowing in the air inlet duct, a third duct receiving thecompressed and cooled air from said air duct section, a power drivenrotor receiving the air from said third duct and operabl to change thepressure energy thereof to kinetic energy and to supply additionalenergy thereto, a turbine driven by the air from said rotor andproviding the power means for the air compressing means receiving airfrom the inlet duct, and a discharge duct for said turbine.

RALPH C. SCHLICHTIG.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 879,392 Livilly Feb. 18, 1908935,743 Collier Oct. 5, 1909 1,781,062 Houston Nov. 11, 1930 1,883,024Smith Oct. 18, 1932 1,965,733 Chamberlain July 10, 1934 2,133,334 RosettOct. 18, 1938 2,186,844 Smith Jan. 9, 1940 2,222,882 Shames Nov. 26,1940 2,419,477 Binder Apr, 22, 1947

